one feature of prep play is that it actually can strengthen the chance of the seemingly implausible to happen in the fiction. If the GM as part of prep had determined that the city has a thriving underground living animals market, and that there is a dubious institution using this to get specimens for arcane experiments; then suddenly adding an entry of "weirdly mutated out of place animal" on the random encounter table the GM make for that city makes perfect sense.
Imagine the players have not heard anything about this underground market, nor the research institution in their interactions in the city so far. Imagine the GM narrating that as you walk singing trough the streets a giant acid spitting octopus crawls out of an alleyway.
<sinp>
In prepped play this suddenly become an obvious mystery to uncover.
This sort of example illustrates why I regard GM-prep-driven play, of this sort, as GM-driven.
There are approaches to prep that differ from "trad" play that are nevertheless apt to introduce mutant beings into the fiction - eg Apocalypse World fronts/threats - but that follows from the fact that one of the principles for the GM, which the players are signing up for in playing the game is, "Barf forth apocalyptica".
In this sort of prepped play, it is not a mystery to uncover in the same fashion as your post (if I've read it correctly) suggests.
In "normal" character driven play this appear a blatant breach of "metaphysics of fiction".
I don't know how you and
@clearstream are using the phrase "metaphysics of fiction".
But in Burning Wheel, the GM introducing their own enthusiasms that do not bear upon the priorities the players have established for their PCs is a departure from the principles that are meant to govern the GM. This is where the following injunction to the
players becomes relevant (I'm quoting Revised p 269; the same text is found in Gold) - players have "duties" to:
use their character to drive the story forward - to resolve conflicts and create new ones . . . to push and risk their characters, so they grow and change in surprising ways . . .
Use the mechanics . . .
Participate. Help enhance your friends' scenes and step forward and make the most of your own. . . . If the story doesn't interest you, it's your job to create interesting situations and involve yourself. . . .
Thus, while there is always the meta-channel, it is not essential. For instance, I did not need to use the meta-channel to tell the GM that I wanted a scene that would focus on Aedhros's bitter alienation from his fellow Elves: I just had to declare the relevant actions,
using the mechanics to create interesting situation and involving myself:
Thoth successfully performed Taxidermy - against Ob 5 - to preserve the corpse, with a roll good enough to carry over +1D advantage to the Death Art test but did not what to attempt the Ob 7 Death Art (with his Death Art 5) until he could be boosted by Blood Magic. And so he sent Aedhros out to find a victim
Aedhros had helped collect the corpse, and also helped with the Taxidermy (using his skill with Heart-seeker), but was unable to help with the Death Art. He was reasonably happy to now leave the workshop; and was no stranger to stealthy kidnappings in the dark. I told my friend (now GMing) that I wanted to use Stealthy, Inconspicuous and Knives to spring upon someone and force them, at knife point, to come with me to the workshop. He called for a linked test first, on Inconspicuous with Stealth FoRKed in. This succeeded, and Aedhros found a suitable place outside a house of ill-repute, ready to kidnap a lady of the night. When a victim appeared, Aedhros tried to force a Steel test (I think - my memory is a bit hazy) but whatever it was, it failed, and the intended victim went screaming into the night. Now there is word on the street of a knife-wielding assailant.
Aedhros's Beliefs are I will avenge the death of my spouse!, Thurandril will admit that I am right! and I will free Alicia and myself from the curse of Thoth!; and his Instincts are Never use Song of Soothing unless compelled to, Always repay hurt with hurt, and When my mind is elsewhere, quietly sing the elven lays. Having failed at the most basic task, and not knowing how to return to Thoth empty-handed, Aedhros wandered away from the docks, up into the wealthier parts of the city, to the home of the Elven Ambassador. As he sang the Elven lays to himself, I asked the GM for a test on Sing, to serve as a linked test to help in my next test to resist Thoth's bullying and depravity. The GM set my Spite of 5 as the obstacle, and I failed - a spend of a fate point only got me to 4 successes on 4 dice.
My singing attracted the attention of a guard, who had heard the word on the street, and didn't like the look of this rag-clothed Dark Elf. Aedhros has Circles 3 and a +1 reputation with the Etharchs, and so I rolled my 4 dice to see if an Etharch (whether Thurandril or one of his underlings or associates) would turn up here and now to tell the guards that I am right and they should not arrest me. But the test failed, and the only person to turn up was another guard to join the first in bundling me off. So I had to resort to the more mundane method of offering them 1D of loot to leave me alone. The GM accepted this, no test required.
Then, repaying hurt with hurt, Aedhros followed one of the guards - George, as we later learned he was called - who also happened to be the one with the loot. Aedhros ambushed him from the darkness, and took him at knife point back to the workshop, where Thoth subject him to the necessary "treatment"
We can pick this apart, and thus see the difference from GM-driven play:
The player and GM together agree that Aedhros can try and conceal himself at a place of likely victims. This could probably happen in any but the most GM-driven of play.
The linked test on Inconspicuous and Stealthy succeeds, and so Aedhros is lurking, ready for a victim. The significance of this, which differs from GM-driven play, is that the success
obliges the GM to frame the next scene, in which Aedhros get to try and kidnap his victim at knife-point. The GM does not have the option to say "nothing happens", or to frame Aedhros into a different sort of encounter.
The attempt at kidnap fails, and so the GM has to narrate a consequence: the escape of the victim, and the word on the street. This could probably happen in GM-driven play. (Though I don't know how D&D actually resolves the attempt at kidnap; if it's via the combat rules, then a PC vs an ordinary person NPC probably can't fail: so what is a climactic moment in the BW play is probably not climactic in D&D play.)
When I implicitly tell the GM what scene I want, by expressly declaring an action - ie walking up the hill of the town towards the wealth residences, quietly singing the Elven lays as per Aedhros's Instinct - the GM goes along with it. And there are three things to notice about this:
First, I am using an Instinct, and so I get to make my Sing test before anything else happens. This is me
using the mechanics to get something interesting to me, in a way that a GM driven game does not permit. (Because in that sort of game, all action declarations are filtered through the GM's prior authority to frame the scene and establish fictional position.)
Second, the GM in BW is not at liberty to (for instance) just frame Aedhros into a confrontation with a dozen guards looking to arrest him - because that would not be a scene that speaks to, and puts pressure on, the priorities that I (the player) have authored for Aedhros. And there is already a scene that does speak to, and put pressure on, those priorities established - namely, Aedhros walking and singing.
Third, the scene is not just a colour scene. The test on Sing is another linked test, tying directly back to the priorities that I (the player) have established for Aedhros, including that
I will free Alicia and myself from the curse of Thoth! So the GM doesn't need to be worrying about introducing something of his own volition and that he thinks will make the game "go": my description of what Aedhros is doing already makes the game "go".
The Sing test fails, and so now the GM has to narrate a consequence - a complication - again having regard to the priorities that I have authored for Aedhros. He chooses to bring home more fully the consequence of the prior failure: a suspicious guard harasses Aedhros. In terms of the priorities I have authored, this fits with Aedhros reputation as ill-omened, his "self-deluded" trait (did he
really think that, by singing the Elven lays, he could set himself against Thoth?), and his Instinct to always repay hurt with hurt (what will he do to the guard?)
I respond by declaring another action: will no Elf come to help Aedhros? This is me, again, using the mechanics - the Circles mechanics - to push things in what I regard as an interesting direction. Will Thurandril, the Elven Ambassador and father of Aedhros's late spouse, whose sent Aedhros spiralling down the path of spite, finally recognise that Aedhros is right? In a GM-driven game, I the player can ask the GM whether any Elves come to help my PC, but I have no mechanical way of making that happen: the GM has unfettered discretion over the geographic and temperamental dispositions of the NPCs.
The Circles test fails, and so the GM has to narrate a consequence, and he doubles down: another guard turns up.
I decide that Aedhros offers the bribe, and the GM says "yes", because this does not put pressure on Aedhros's Beliefs, Instincts etc. There are no Beliefs or other elements there about obedience to authority, or always getting my way with guards, or whatever. The interesting question remains, what will Aedhros do next?
Again acting on Instinct, and thus pre-empting the GM's ability to introduce new complications into the scene,
before I get my test, Aedhros repay hurt with hurt. And this time it succeeds (the actual play report doesn't describe what the test was, but at a guess it would have been Knives augmented by Stealth and Inconspicuous), and so I get my intent and task: George is captured, ready for Thoth to subject him to "treatment". In a GM-driven game, the GM would not be obliged to allow the check to kidnap George, but could introduce other stuff that they wanted to; and once George had been captured would also be able to introduce more stuff in between the capture and the return to Thoth.
I hope this detailed analysis helps illustrate how events, and the content of the fiction, are not flowing predominantly from the GM. As a player, I am not having to work out
what the GM has in mind by introducing an element. I am not trying to solve mysteries posed to me by the GM. There are no low-stakes action declarations to try and work out what is
really at stake in the situations the GM describes.
This is a particular way of RPGing. It is one that I happen to enjoy very much, both as player and as GM. It can be done using systems other than Burning Wheel: for instance, I've done something like it using Rolemaster and using AD&D. But these are not as good for this approach as is BW, because their mechanics are less well-suited. They have no analogue to the Circles test, for instance. And in RM the use of the Sing test to create an augment would require a bit of a departure from a strict reading of the rules. Those systems also sometimes generate consequences that are at odds with (re)framing scenes in a way that keeps player-determined PC priorities to the fore. The GM therefore has to do more work "bridging" all these gaps between what the mechanics can do, and what needs to be done to achieve the desired sort of play experience.
If someone doesn't
want this sort of play - for instance, their preference is to try and solve mysteries posed to them by the GM - then of course Burning Wheel won't appeal to them, and nor will the techniques that it uses.